1. Technical Field
The present invention relates to medical treatment involving pressurized oxygen, and more specifically to hyperbaric pressure chambers for patient accommodation. In particular, the invention provides chambers of modular construction, capable of size adjustment to meet specified requirements. This allows treatment facilities some flexibility to respond to fluctuating demand, both increasing and decreasing, for hyperbaric oxygen treatment.
2. Background Art
Traditional hyperbaric oxygen treatment (HBO) requires a patient to breathe 100% oxygen while at a pressure greater than ambient, i.e.  greater than 1 atmosphere absolute (ATA). HBO is an established technology to help resolve certain chronic, recalcitrant, expensive, or otherwise challenging medical problems. Treatment can be carried out in either a monoplace or multiplace chamber. The former accommodates a single patient and the entire chamber is pressurized with 100% oxygen which the patient breathes directly. A multiplace chamber may hold two or more patients, observers, and support personnel. It is pressurized with compressed air and the patients breathe 100% oxygen via a mask, head tent, or endotracheal tube. According to the Undersea Hyperbaric Medical Society, breathing 100% oxygen at 1 ATA of pressure or exposing isolated parts of the body to 100% oxygen does not constitute HBO therapy; the patient must inhale the oxygen in a pressurized chamber. Current research indicates that pressurization should be to 1.4 ATA, or higher, for HBO to be most effective. The elevated pressure promotes super saturation of oxygen in blood plasma and tissue fluids. As a result, the body utilizes oxygen more efficiently and promotes healing functions.
Monoplace or single patient hyperbaric chambers are commonly fabricated from a transparent acrylic plastic tube with machined metal end plates or caps. The patient usually lies inside the confined space of the acrylic tubular compartment and breathes 100% oxygen for the duration of the treatment. Monoplace chambers are now available in different diameters for enhanced patient comfort. Other design variations on the traditional monoplace concept include chambers made of welded stainless steel with a medical attendant pod to provide xe2x80x9chands-onxe2x80x9d care during treatment and very large acrylic tubes for treatment of two patients simultaneously. As an alternative to fabrication of monoplace chambers from relatively rigid materials, a variety of inflatable chambers provide individuals with on-site treatment for such situations as rescue operations and severe oxygen deprivation. As an example, inflatable HBO chambers constructed from flexible fabrics are carried by divers as a precaution against the bends which is caused by a too rapid ascent from deep diving activities.
One advantage of monoplace chambers is ease of installation, since they are relatively small and usually designed for maneuverability. In clinics or hospitals they conveniently use existing services, with minimal need for facility services and utilities such as electrical, oxygen, etc. Other benefits include ease of use, since controls are few, relative portability, as they are typically mounted on wheels, and low cost compared to larger multiplace hyperbaric systems. Representative disadvantages are: no xe2x80x9chands onxe2x80x9d care by medical providers, confined space for the patient, increased fire risk due to the large amount of 100% oxygen in the chamber, a limited service life of the acrylic tube, and high staff to patient ratio.
Large multiplace hyperbaric chambers are fabricated of welded steel and commonly configured as a horizontal, generally cigar-shaped cylinder of varying lengths and diameters. Many have a rectangular entry ways for patient access. Ambulatory patients enter the chamber and sit in a wheel chair or on a provided seat. Non-ambulatory patients normally lie on stretchers or other types of litters during treatment sessions. The presence of multiple patients normally requires trained medical personnel who assist the patients in the use of the oxygen equipment and provide xe2x80x9cfront linexe2x80x9d medical response if needed during treatment. Advantages of the multiplace hyperbaric chamber include: improved staff to patient ratio which reduces costs, the ability to provide xe2x80x9chands onxe2x80x9d care, improved direct observation of patient status, and reduced fire risk. Regarding conventional multiplace systems, disadvantages include: higher initial procurement and installation costs, larger personnel pool, greater complexity in operation and chambers that are permanently located and not easily transported. Because of the size and weight of these large metallic structures, and, due to being constructed off-site, they usually require major building modifications for ground floor or basement installation. Still further, it has come to be appreciated that it is a commonly held belief throughout the HBO field that a sustained patient treatment load of at least eight patients per day is required to justify the installation and operation of a multiplace hyperbaric facility. Obviously, fewer patients are required to justify monoplace chambers.
Small treatment facilities with restricted funding would benefit from being provided flexibility in treatment configurations. As treatment activity increases beyond monoplace capabilities, however, a small medical facility traditionally had to acquire the funding and space needed to install currently available, large multiplace chambers. Acquisition of funds and space may present an insurmountable obstacle which could prevent a small facility from responding to an increasing volume of patients. This situation is undesirable for both patients and treatment providers who may procure additional monoplace chambers, unable to benefit from the added efficiencies and profit associated with the operation of multiplace units.
Clearly, a need exists for a hyperbaric treatment compartment that is capable of expansion to provide additional internal space without marked increase in the space occupied by the unit as a whole. Because of the wide disparity in characteristics and suitabilities between monoplace and multiplace hyperbaric units, the desirability of intermediate options has become clear. Further yet, the best of both configurations could be reaped from a variably adjustable system having possible configurations across a range including monoplace, multiplace and gradations therebetween. In this way, a very attractive feature of enabling the increase of treatment space by reconfiguring an existing hyperbaric unit would be provided in order to accommodate a surge of patients or to respond to a steady increase or decrease in demand for the treatment.
In view of the above described deficiencies associated with the use of conventionally designed hyperbaric oxygen chambers, the present invention has been developed to alleviate these drawbacks and provide further benefits to the user. These enhancements and benefits are described in greater detail hereinbelow with respect to several alternative embodiments of the present invention.
In the disclosed embodiment, the present invention alleviates the drawbacks described above with respect to size and cost limitations of current monoplace and multiplace hyperbaric chambers. The incorporation of several additionally beneficial features, according to the present invention, allows a medical facility to install a size-adjustable multiplace HBO chamber that corresponds to the needs of an existing number of patients. This provides a flexible approach to the management of patient care that was not previously known.
Description of multiplace hyperbaric oxygen chambers, according to the present invention, requires reference to their modular construction, relative ease of assembly and disassembly, portability and installation without significant building modification to provide the space they occupy. The feature of modular construction is particularly important for selecting the combination of parts to satisfy selected dimensions based upon the number of patients to be treated. A minimum number of parts forms what may be referred to as a mini-chamber, accommodating maybe two or three patients. Adding modules results in expanding the size of the treatment chamber until it is comparable in dimensions to traditional multiplace chambers. Application of the term xe2x80x9cmini-multixe2x80x9d to chambers constructed according to the present invention, indicates the flexibility of the modular concept. Modules include flat or curved panels. The panels may also be in sectional pieces to allow freedom of design, efficient space utilization, and optimum pressurization inside the chamber. Sections and modules, for forming the chamber, require a means of interconnection for structural integrity and sealed boundaries at the sites of connection. Sealed boundaries prevent escape of air and oxygen while allowing pressure inside the chamber to increase to the level needed for effective treatment. Typical design criteria require an HBO chamber to handle pressures of about 6 atmospheres absolute (ATA) with relative ease. Removable connectors such as nut and bolt combinations provide suitable means for assembling and disassembling chambers according to the current invention. Flexible seals, gaskets and fluid sealing materials, placed between modules and sections, prevent gas leakage and loss of pressure from a chamber. Before assembly, section and module manufacture produces parts small enough for easy portability. The parts are usually small enough to pass through a standard sized door frame allowing delivery for chamber assembly inside a building, without having to structurally modify the building. When needed, the modular chamber may be dismantled, moved and then conveniently re-assembled at a different location.
Exemplarily, a modular hyperbaric chamber for treatment of at least one patient, according to the present invention, includes at least one spacer module having a first flange and a second flange. The spacer module may be formed from a plurality of sections, with each section including opposing lip portions to form air-tight junctions. A first half cylinder module includes a first peripheral contact edge for releasable sealed connection to the first flange of the spacer module. Similarly, a second half cylinder module includes a second peripheral contact edge for releasable sealed connection to the second flange of the spacer module. An access door formed in at least one of the half cylinder modules provides access to the interior of the chamber.
In accordance with the foregoing, the invention is a variably sized, hyperbaric chamber, of modular construction, that is easily assembled at a medical treatment facility. The chamber is movable after dismantling. Apart from its modular construction, innovative features, according to the present invention, include the use of parts sized to pass through a standard doorway. Still further, temporary connections between parts for convenient assembly and disassembly and size adjustment is achieved by the addition of variably dimensioned stretch modules also referred to herein as spacer modules. A pressure lock, incorporated into a rectangular doorway enables entrance and egress by patients and support personnel.
The beneficial effects described above apply generally to the exemplary embodiments disclosed herein of the modular hyperbaric oxygen chamber. The specific structures through which these benefits are delivered will be described in detail hereinbelow.